package com.xiaoyang.filter;


import com.alibaba.fastjson.JSON;
import com.xiaoyang.common.BaseContext;
import com.xiaoyang.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * @auther XiaoYang
 * @DATE 2022/12/10-13:50
 */
@Slf4j
@WebFilter(filterName = "LoginCheckFilter",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    //进行路径比较    ->  路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request =  (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //过滤器具体的处理逻辑如下：
        //1、获取本次请求的URI
        String requestURI = request.getRequestURI();
        log.info("拦截到请求:{}",requestURI);
        //定义不需要拦截的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };

        //2、判断本次请求是否需要处理
        boolean check = check(urls, requestURI);
        //3、如果不需要处理，则直接放行
        if (check){
            log.info("本次请求:{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }
        //4-1、判断登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("employee") != null){
            log.info("用户已登录，用户id为:{}",request.getSession().getAttribute("employee"));

            //使用线程安全来储存当前登录id
            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request,response);

            return;
        }
        //4-2、判断移动端登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("user") != null){
            log.info("用户已登录，用户id为:{}",request.getSession().getAttribute("user"));

            //使用线程安全来储存当前登录id
            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request,response);

            return;
        }


        log.info("用户未登录");
        //5、如果未登录则返回未登录结果,通过输出流的方式向客户端响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));

        return;

    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            //PATH_MATCHER.match对比请求路径是否一致
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) {
                return true;
            }
        }
        return false;
    }

}
